The present invention relates to a dielectric device having a high permittivity and good insulation characteristics.
Conventional capacitors are constituted, for instance, by first forming an N.sup.+ -type drain region on part of a Si substrate, then forming a SiO.sub.2 layer thereon, and finally forming a polysilicon electrode on the SiO.sub.2 layer. However, such capacitors cannot provide a sufficiently large permittivity. With a recent increase of the degree of integration of this type of devices and a resultant reduction of the electrode area, it has been desired to utilize a material having a high permittivity.